any stores like Radio Shake (brick and mortar)/fios equipment help

I have fios home, I keep having problems with the cable that connects from the useless battery back up to the modem/router.  I have been jumping through hoops with verizon all afternoon just trying to track down a replacement cable or battery back up box (whole box, not just the battery).  Are there any stores that are similar to how Radio Shake used to be with knowledgeable workers who would be able to track down a new cable if it exists or someone that can help me identify a used replacement I can get off ebay.  My box is from 2009.  I have no clue if I could use a 2020s style box or if there is a cord that can go from the wall directly to the router/modem...skipping the useless battery back up.

its actually the cord that goes from the battery back up to the Optical Network Terminal (i think).  it has those thin metal prongs that get easily bent are are near impossible to straighten, and tends to be knocked out easy..

jmitw said:

I have fios home, I keep having problems with the cable that connects from the useless battery back up to the modem/router.  I have been jumping through hoops with verizon all afternoon just trying to track down a replacement cable or battery back up box (whole box, not just the battery).  Are there any stores that are similar to how Radio Shake used to be with knowledgeable workers who would be able to track down a new cable if it exists or someone that can help me identify a used replacement I can get off ebay.  My box is from 2009.  I have no clue if I could use a 2020s style box or if there is a cord that can go from the wall directly to the router/modem...skipping the useless battery back up.

its actually the cord that goes from the battery back up to the Optical Network Terminal (i think).  it has those thin metal prongs that get easily bent are are near impossible to straighten, and tends to be knocked out easy..

Can you take a picture of what you are referring to? It's possible that I or some other packrat has one in one of their junk drawers. 

Yeah, a picture or two would be useful. I'm having some trouble visualizing the setup.